Search results for " composition"
showing 10 items of 1437 documents
Rare earths and trace elements contents in leaves: A new indicator of the composition of atmospheric dust
2017
The relationship between the trace element distribution in atmospheric particles and leaves of some exposed plants in the environment was recently demonstrated. This indication would suggest that the trace element analysis of leaves in these plants could provide information about the composition, nature and origin of the atmospheric dust dispersed in the environment. In order to corroborate this hypothesis, the distribution of trace elements and Rare Earths were studied in leaves of some endemic plants, in the atmospheric fallout and in soils of rural, urban and industrial ecosystems in Sicily. These elements have been chosen to discriminate the source and nature of different source on atmo…
Microbiological and physico-chemical composition of sewage sludge derived from the food industry=Skład mikrobiologiczny i fizykochemiczny osadów ście…
2013
Abstract The aim of the study was to analyze the microbiological and physico-chemical composition of sewage sludge from the food industry. The research material was dewatered sewage sludge with and without lime, derived from the water and drink production plant in the Opole region, obtained for testing in March 2013. Physico-chemical analysis included the determination of: pH, temperature of sludge, sedimentation properties, the dry weight, mineral substances, biogenic elements and heavy metals. Microbiological evaluation included quantitative and qualitative determination of mesophilic, psychrophilic and potentially pathogenic microorganisms. Sewage sludge with and without lime characteriz…
Polar organic marker compounds in PM2.5 aerosol from a mixed forest site in western Germany
2008
The molecular composition of PM2.5 (particulate matter with an aerodynamic diameter2.5 microm) aerosol samples collected during a very warm and dry 2003 summer period at a mixed forest site in Jülich, Germany, was determined by gas chromatography/mass spectrometry in an effort to evaluate photooxidation products of biogenic volatile organic compounds (BVOCs) and other markers for aerosol source characterization. Six major classes of compounds represented by twenty-four individual organic species were identified and measured, comprising tracers for biomass combustion, short-chain acids, fatty acids, sugars/sugar alcohols, and tracers for the photooxidation of isoprene and alpha-/beta-pinene.…
Characterization of the Etna volcanic emissions through an active biomonitoring technique (moss-bags): Part 1 – Major and trace element composition
2013
Active biomonitoring using moss-bags was applied to an active volcanic environment for the first time. Bioaccumulation originating from atmospheric deposition was evaluated by exposing mixtures of washed and air-dried mosses (Sphagnum species) at 24 sites on Mt. Etna volcano (Italy). Concentrations of major and a large suite of trace elements were analysed by inductively coupled mass and optical spectrometry (ICP-MS and ICP-OES) after total acid digestion. Of the 49 elements analysed those which closely reflect summit volcanic emissions were S, Tl, Bi, Se, Cd, As, Cu, B, Na, Fe, Al. Enrichment factors and cluster analysis allowed clear distinction between volcanogenic, geogenic and anthropo…
Chemical composition of lipophilic extractives from grey alder (Alnus incana)
2013
The chemical composition of the lipophilic extractives in the hexane extracts from grey alder bark, knotwood, and cones has been investigated by gas chromatography and gas chromatography-mass spectrometry. The efficiency of two extraction methods was compared. The highest amount of lipophilic extractives (about 9% of o.d. material) was observed in grey alder cone, while the lowest (about 3%) was found in knotwood. The three different morphological parts of alder showed significant differences not only in the content but also in composition of extractives, namely fatty acids, triglycerides, and triterpenes. The main identified compounds were triterpenoids (lupen-3-one, lupeol, betulone, betu…
Resistance of Conifer Needle Polyolefin Composites (CNPCs) Against Biodecomposition Caused by Fungi
2017
This study describes the resistance of composites filled with conifer needles to biodecomposition processes caused by a single strain of Aspergillus niger as well as by a consortium of microorganisms present in the compost substrates (forest or spent mushroom composts). The impact of various types of conifer needles on the growth of A. niger was studied to determine whether the filler can show the fungistatic effect. The changes in chemical composition of the composites surfaces were examined using attenuated total reflectance Fourier transform infrared spectroscopy (FTIR/ATR). The results showed that the fungistatic effects of conifer needles polyolefin composites (CNPCs) were associated w…
Vides apstākļu ietekme uz mikro- un makroelementu saturu pārtikas produktos Latvijā
2014
Bez vitāli svarīgo mikro- un makroelementu ieneses pārtikā no vides (augsnes, ūdens un gaisa) ir iespējams arī barības ķēdes, t. sk., pārtikas piesārņojums ar toksiskiem vai potenciāli toksiskiem elementiem, piemēram, As, Cd, Hg, Pb. Promocijas darba mērķa ietvaros tika veikta Latvijā iegūtu pārtikas produktu paraugu mikro- un makroelementu sastāva kvantitatīvā analīze, lai noskaidrotu vides apstākļu ietekmi uz elementu koncentrāciju un ieneses ceļiem pārtikā. Papildus, lai vērtētu elementu biopieejamību barības ķēdē, tika veikta eksperimentāla pārtikas kultūraugu audzēšana mākslīgi piesārņotā augsnē. Iegūtie dati liecina par vairāku dabiskas un antropogēnas izcelsmes vides apstākļu, piemēr…
Equilibrium swelling properties of polyampholytic hydrogels
1996
The role of counter ions and ion dissociation in establishing the equilibrium swelling of balanced and unbalanced polyampholytic hydrogels has been investigated experimentally and theoretically. The swelling dependence on both the net charge offset and the external bath salt concentration has been examined using an acrylamide based polyampholytic hydrogels. By careful consideration of the swelling kinetics, we illustrate the effects of ion dissociation equilibria and counter ion shielding in polyampholytic hydrogels near their balance point where both polyelectrolyte and polyampholyte effects are present. The theory considers a Flory type swelling model where the Coulombic interactions betw…
Chemical Composition and Antimicrobial Activity of the Essential Oil from Flowers of Eryngium triquetrum (Apiaceae) Collected Wild in Sicily
2016
The chemical composition of the essential oil from flowers of Eringium triquetrum Vahl. collected in Sicily was evaluated by GC and GC-MS. The main components were pulegone (50.6%), piperitenone (30.5%) and menthone (7.0%). Comparison of this oil with other studied oils of Eringium species is discussed. The oil showed good antibacterial and antifungal activities against some microorganisms that infest historical art works.
Hunting for valuables from landfills and assessing their market opportunities A case study with Kudjape landfill in Estonia
2017
Landfill mining is an alternative technology that merges the ideas of material recycling and sustainable waste management. This paper reports a case study to estimate the value of landfilled materials and their respective market opportunities, based on a full-scale landfill mining project in Estonia. During the project, a dump site (Kudjape, Estonia) was excavated with the main objectives of extracting soil-like final cover material with the function of methane degradation. In total, about 57,777 m3 of waste was processed, particularly the uppermost 10-year layer of waste. Manual sorting was performed in four test pits to determine the detailed composition of wastes. 11,610 kg of waste was…